Assume an ordinary user 'user1' has a file 'abc' under the current directory, user1 want to execute this file. When he type 'abc' in the "$" prompt, the system reports an error, so the possible reason for this error is:(1) The value of the system variable 'PATH' of user1 does not include the current directory, so the system cannot find the file.(2) User user1 does not have executable permissions of 'abc'.(3) The current directory of user1 does not have executable permissions.

A. (1)
B. (1)(2)
C. (1)(2)(3)
D. (2)(3)